Pressing an operation part of a hardware button causes an internal switch of the electronic apparatus to be pressed down. The operation part is exposed to the outside of the electronic apparatus. To press down the switch accurately when the hardware button is pressed, the button and switch are disposed close to each other. Thus, water entering into the inside from around the button may easily reach the switch and a substrate on which the switch is mounted. If the water reaches the substrate, the electrical system of the substrate may short out.
To deal with this, Patent Literature 1, for example, discloses a switch apparatus comprising a structure for draining liquid, which enters into the inside, to the outside. The apparatus disclosed in Patent Literature 1 includes a knob which serves as an operation part, and a reception part constituted by a flange portion and an upright wall portion. The housing of the apparatus includes a drain passage that is opened toward the outside.
The flange portion is a flat surface extending in a direction orthogonal to the direction in which the knob is pressed, and the upright wall portion serves as a peripheral wall of the flange portion.
In the flange portion, there is formed a water reception passage extending toward a portion in which water is drained. Further, an opening is formed at an end of the water reception passage. The above-mentioned drain passage is provided at a position lower than the opening. Water entering into the inside from around the knob and received by the reception portion flows through the water reception passage, flows out from the opening of the water reception passage down to the drain passage, and then flows out to the outside.
Note that the switch apparatus described in Patent Literature 1 is a so-called direct-acting button in which an operation of pressing the nob directly moves the nob to make a tip of the nob press the switch.
In addition, the switch apparatus described in Patent Literature 1 is designed to be used in such a manner that the switch apparatus is arranged to tilt in a drainage direction. That is, since tilting the switch apparatus makes the water reception passage and drain passage tilted in the drainage direction, water received by the reception portion flows smoothly toward the drainage direction.